Fixed
- An essential dragged down into the list has the same place after the last folder, above the line, as a tab does: it went into the folder sooner and passed the line almost at once, so that place was a sliver.
- No stray line over a closed folder's arrow (seen on Windows at 125% scaling): the arrow is drawn as a line of its own rather than cut out of a square, whose edge showed once the arrow was turned.